Bulldozer



J. KUCHAR BULLDOZER A ril 27, 1937.

Filed Sept. 13, 1934 5 Sheets-Sheet 1 Marika- .jose o/i Mar xz m mu mtApril 27, 1937. J KUCHAR 2,078,636

BULLDOZER Filed Sept. 13, 1934 5 Sheets-Sheet 2 BULLDOZER Filed Sept.13, 1934 5 Sheets-Sheet 4 April 27, 1937. J K R 2,078,636

BULLDOZER Filed Sept. 13, 1954 5 Sheets-Sheet 5 Jase 0k Mar 22 (95 a; aK24 ,(1M; ,,);1Mf/La Patented Apr. 27, 1937.

l-TED STATES amoozsn Joseph Kuchar, Chicago, 111., assignor to AtheyTruss Wheel Company, Chicago, 111., a corporation of IllinoisApplication September 13, 1934, Serial No. 743,791

11 Claims.

This inventionrelates to bulldozers and has for its principal object toprovide an improved bulldozer.

A further object of the invention is to provide a bulldozer in which theoperating mechanism is more compact and more effective.

A further object of the invention is to provide an improved mounting forthe bulldozer upon a tractor or the like.

A further object of the invention is to provide an improved equalizingsupporting system for a bulldozer.

Other objects, advantages, and capabilities. of the invention willappear from the following description of a, preferred embodiment thereof1 illustrated in the accompanying. drawings, in

which 1 r Figure 1 is a side elevation of a tractor equipped with myimproved bulldozer, part of 20 the tractor beingbroken away toillustrate the v pump which supplies pressure fluid for the actuation ofthe bulldozer; Q

Fig. 2 is a. plan view showing the bulldozer and pump in full lines andthe tractor in phantom;

Fig. 3 is a sectional detail view taken on the line 33 of Fig. 2 showingthe location and arrangement of the cylinder;

-Fig. 4 is a sectional view taken through the cylinder on the line l4 ofFig. 3;

section, showing the bulldozer at its highest point of adjustment;

g. 6 is a similar view showing the bulldozer at lowest point ofadjustment;

Fig. 7 is a'deta'il view, partly in section, showing part of theequalizing structure;

Figs. 8 and 9 are diagrammatic front and side elevational views showingthe relation of parts when-the forward part of a wheeled structure ispassing over an obstruction, and

Figs. 10 and 11 are similar views showing the relation of parts when therearward part of a wheeled structure is passing over an obstruction.

Referring to the drawings, the reference numeral l0 designates a tractorupon which the bulldozer, designated as a whole by the reference numeralIi, is mounted. The tractor I0 is v of the conventional type restingupon wheeled structures 12 on either side. The wheeled structure l2comprises internal rigid elements such as l3, which provide a supportfor a belt or track 14, whichbelt passes over wheels I5 and I 6 carriedby said rigid elements 13. The whole wheeled structure I2 is pivotallyconnected to the body of the tractor by the axle of the wheel Fig. 5 isan elevational detail view partly in,

15. The forward end of the tractor is supported on the wheels l2 by'means of springs H on either side which project outwardly towards thewheels l2 and ,rest upon rigid elements l3 thereof.

It is convenient to remark here that when the forward end of one of thewheeled structures l2 meets an obstruction it rides up over it and isdeflected upwards from the position shown in Fig. 1, rotating incounter-clockwise direction about'the axle of the wheel l5, to a limitedextent. It will'be recognized that thedeflection .thus produced willhave a greater influence at points on the wheeled structure remote fromthe axle of the wheel 15 and will have very little influence on pointsnear this axle.

At a position near the axle of the wheel 15 is rigidly mounted on therigid part of the wheeled structure l2 .a pivot member l8 for the mainarms IQ of' the bulldozer. These arms I9 are preferably large tubes ofgreat strength, which have mounted on their rear ends socket members 20which are provided with suitable bearings for the reception of thepivots la. The forward ends of the arms I9 are rigidly secured to hous-'ings 2!, which support the main plate 22 of the bulldozer head. Thismain-plate extends across the front of the tractor and across the armsl9 and housings 2| so as. to form a'rigid integral b'ulluozer head. Atits lower edge and on its forward side the plate 22 is provided with acut- .ting edge 23 which is removablybeing held in position by means ofbolts.

The main plate 22 of the bulldozer head is n substantially concave asviewed from the front, and. its upper edge is bent back rearwardly anddownwardly to provide a strong upper rim 2i. The mainv plate 22 isreinforced by suitable supporting elements on its rear side so as toprevent distortion during operation. On its rear side adjacent its loweredge the plate 22 is strengthened by an angle iron 25. This angle iron25 extends across the whole width of the plate 22 and-is secured theretoby means of rivets or bolts. The reinforcement for the plate 22 maysuitably 'comprise a transverse beam 26 located in spaced relation tothe plate 22 and rigidly mounted at each end upon the housings 2|. Thebeam 26 may suitably be formed from angle iron and its center portionmay suitably be bowed forward somewhat, as best seen in Fig. 2.

The main plate, 22 of the bulldozer head is also reinforced by aplurality of vertical plates 29, the forward edges of which conform tothe rear face of the main plate 22. The plates 29 comprise flanges bywhich they are secured to the main plate'22, transverse beam 26 andangle iron .25. Certain of these plates 29 extend upwardly and fitsnugly into the rim 24 at the up- .per edge of the plate 22. Theselatter plates 29 support bearings 36 for a rocking shaft 3| whichextends transversely of the bulldozer and projects laterally on eitherside of the front end of the tractor. Two o'f the plates 29 adjacent theright-hand end of the main plate 22 are provided with bearings 32 forthe trunnions 33 of a hydraulic cylinder 34. These two plates 29 areconnected by atransverse rear plate 35 and transverse upper plates 36 sothat the cylinder 34 is substantially enclosed. The upper plates 36 areprovided with an opening which. provides for free movement of thecylinder 34 and the piston rod 31 which projects upwardly, as shown inFig. 3. The piston 38 is mounted on .the lower end of the piston rod 31and is located within the cylinder 34. The upper "end of the piston rod31 is pivotally connected to an arm. 39',which is keyed upon the rockingshaft 3|.

The arm 39 is preferably a casting and is of substantial width. On itsunder side it is provided with two downwardly extending webs 48 whichare provided with openings for the reception of a pin 4|. upper end ofthe piston rod 31 and the pin 4| is adapted to pass through an openingtherein. The pin 4| also extends through an opening near theforward endof a link 43 so that the link 43 is rigidly connected to the arm 39. Thepin 4| is held in position by means of a cotter pin. The forward end ofthe link 43 is also keyed or otherwise rigidly secured to the rockingshaft 3| so as to turn therewith.

As best seen in Fig. 2, the cylinder 34 and associated arm 39 aremountedadjacent one end of the bulldozer. A similar arm 39 and link 43 aremounted on the rocking shaft 3| adjacent the other endof thebulldozer.This arm 39 and link 43 are connected together exactly the samev way asthe arm 39 and link 43 just described,

but since it is preferred to provide only one cylinder, there is nopiston rod 31 associated with; the left-hand arm 39.

The links-43 extend rearwardly from the rocking shaft 3| and their rearends are pivotally mounted in the bifurcated upper ends of a U- shapedbar 44 which extends transversely below the forward end of the tractor,its upwardly directed legs being-located on either side. of saidforwardend. At its center the U-shaped bar 44 is provided with-a verticalbearing 45 whereby it is .pivotally mounted upon a normally-verticalpivot 46. The pivot 46 carries at its lower end a head 41 which receivesa substantially horizontal pivot 48 located in the longitudinaldirection of the tractor. The head 41 is located within an opening 49 inthe center of a transverse beam 58 and the pivot 48 projects throughopenings elements I3 of, suchwhee'led structures.

.universal joints 52;preferably include balls 54' which-are freelyslidable 'on the ends of the beam 58 so as-to accommodate end play.

The bulldozer head is supported by""feet 54 X which have bearingsurfaces adapted-torest on the ground. The feet 54 compriseshanks 55 Ahead 42 is mountedor'i the r which project upwardly into the housings2|. The housings 2| and the shanks 55 are provided with openings adaptedto be brought into alignment and to receive pins 56 to maintain the feet54 in desired position of adjustment with respect to the bulldozer head.

The bulldozer is controlled from the drivers seat 57 of the tractor H]by means of the control lever 58 of the pump 59. This pump may be of anysuitable type provided it is equipped with two lines 60' and 6| and avalve control whereby pressure fluid may be supplied to either of themat will and prevented from returning until it 'is desired to change theadjustment of the bulldozer. The pump 59 shown in the drawings maysuitably be that described and claimed in my Patent No. 2,018,269, andentitled Fluid pressure mechanism. The pump control lever 58 has fivepositions, the leverbeing shown in full lines in Fig. 1 in the initialposition a. In this position the clutch connecting the engine When thelever 58 is moved to position e pressure fluid is supplied to the pipe6|, the pipe 60 being connected for return of fluid to the tank 62.

The pipes 68 and 6| extend along the right-hand side of the tractor IDto the front of the tractor and are connected by hoses 63 and 64respective-- ly to the lower and upper ends of the cylinder 34.

It will readily be understood, particularly from Figs. 5 and 6, that thesupply of pressure fluid to the lower end of cylinder 34, as a result ofthe movement of the lever 58 .to position 0, causes a downward movementof the bulldozer head. When, however, pressure fluid is supplied to theupper end of the cylinder 34, as a result of the movement of the lever58 to position e, the bulldozer head is moved upwardly; When the controllever 58 is moved to position (1, the pump is by-passed and the pipes"66 and-6| are shut off from the pump and the tank 62. Consequently theposition of the bulldozer head depends upon its mechanical mounting, theclosing of the pipes 68 and 6| serving to prevent any movement of thepiston 38.

Owing to the mounting of the cylinder 34 upon the head of the bulldozerand the characteristic leverage system to which its piston rod 31! isattached, I am enabled to control the position of the bulldozer headthrough a wide range, in fact, through a distance much greater than thelength of the cylinder, as may readilybeseen by 'a comparison of Figs. 5and 6. I

One of. the outstanding advantages of the present machine is that thebulldozer head has a great'tendency to remain; in horizontal position,assuming work to start from a horizontal base. This characteristicgreatly facilitates the attainment of a level surface since anyirreguralities initially. present can beminimized and worked out by thesimple, expedient of taking another cut. To explain more fully themanner in which the equalizing and automatic leveling eficts of thepresent bulldozer are obtained, let

us consider the diagrammatic illustrations, Figs:

8, 9, 10, and 11. In Figs. 8 .and 10 the wheeled structures |2 have.been working on. substantially level ground. Let us assume that aboulder structure H. The forward end of the wheeled structure l2 passesover the boulder and is elevated in the manner shown in Fig. 9, beingrotated bodily to some extent in the clockwise direction (as viewed inFig. 9), by the axle of the wheel I5. This rotation has practically noeffect upon the pivot l8 for the left-hand arm IQ of the bulldozer, forthe reason that the pivot I8 is very near the center of the wheel l5. Aswill readily be understood from Fig. 8, the left-hand arm 53 isconsiderably elevated by the presence of the boulder 65 under theforward part of the left-hand wheeled structure, because this arm 53 ismounted on that structure and projects forwardly therefrom. Consequentlythe lefthand end of the beam 50 (on the right, as viewed in Fig. 8) issubstantially elevated relative to the left-hand end of the beam 50.Owing, however, to the mounting of the U-shaped bar 44 at the center ofthe beam 50, the only effect is to elevate the bar 44 to some extentwithout sloping the head of the bulldozer to any. substantial extent.The head of the bulldozer is-dia-' grammatically shown in dash-anddotlines in Fig. 8 in order not to obscure the view of the beam 50 and thebar 44 which, of course, are behind the bulldozer head.

As the tractor continues forwardly the rear end of the left-hand wheeledstructure l2 passes over the boulder 65, and while it is immediatelybelow the wheel I 5 the boulder does substantially elevate the lefthandpivot l8. This upward .displacement of the pivot l8 takes place to asubstantial extent only for the short distance of travel and while itundoubtedly causes some tendency to move the head of the bulldozer outof horizontal, this tendency is prevented by the feet 54 which are stillriding-upon the horizontal work face which has just been cut by the headof the bulldozer owing to the equalizing action just described. Owing tothe length of the arms 19, the twist of the bulldozer head and mountingnecessary for the preservation of a substan-' tially horizontal cuttingedge is provided without damage to the structure. It will readily beunderstood that by backing up and taking another cut any slightirregularities are removed from the work surface, together withobstructions such as the boulder 65. A large amount of work can veryreadily be performed since repeated adjustments on the part of theoperator. in order tostraighteri the cutting blade to preserve a flatsurface, such as were necessary in previously constructed bulldozers,are completely obviated.

Although the invention has been disclosed in connection with thespecific details of a preferred embodiment thereof, it must beunderstood that such details are not intended to be limitative of theinvention except in so far as set forth in the accompanying claims.

Having thus described my invention, what I claim as new and desire tosecure by LettersPatent of the United States is:

1. In combination, a tractor having track laying wheel structurespivotally mounted on the tractor adjacent their rear ends, saidstructures having a forwardly extending rigid framework resilientlysupporting .the tractor, a bulldozer pivotally mounted on the rigidframeworks of the wheeled structures adjacent their pivots, and atransverse beam pivotally supported by the frameworks of both wheelstructures at a forward position thereon, for supporting the bulldozerblade substantially horizontal.

2. In combination, a tractor having track laying wheel structurespivotally mounted on the tractor adjacent their'rear ends, saidstructures having a forwardly extending rigid framework resilientlysupporting the tractor, a bulldozer pivotally'mounted near the rear ofthe tractor and having a blade structure, links pivotally mounted onsaid blade, a transverse member pivotally connected to said links, and asecond 'transverse member pivotally connected to the first saidtransverse member at a central posi tion, the last said member beingsupported by said frameworks at positions considerably forward of theirpivoted mounting on the tractor.

3. A bulldozer comprising a blade and two rearwardly extending limbswhereby the blade -may be pivotally mounted on a tractor, linkspivotally mounted on the blade at their forward ends, equalizing meansconnected to the rear ends of said links and adapted to be connected toa tractor, and power means on the blade and operatively connected tosaid links whereby said links may be rotated relatively to the blade toadjust the elevation of said blade.

4. A bulldozer comprising a blade and two I rearwardly extending arms,whereby the blade may be pivotally mounted on a tractor, a bar rotatablymounted on the blade and extending longitudinally thereof, rearwardlyextending arms rigidly mounted on said bar an equalizer beam adapted tobe carried by the tractor and having the rear ends of last said arms bepivotally connected thereto, and power means on said blade for rotatingsaid bar to adjust the elevation of the blade.

5. A bulldozer comprising a. blade, means for ,pivotally supporting saidblade on a vehicle on a horizontal axis, arms rearwardly extending fromsaid blade and held rigid thereon, a transverse beam to which said armsare pivotally connected, a second beam pivotally connected to the firstsaid beam, and means for mounting the second said beam on independentwheeled structures pivotally mounted on said vehicle.

-6. In combination, a tractor having relatively long track laying wheelspivotally mounted near their rear ends on an axle, means supporting thetractor on the wheels forwardly of said axle, said wheels comprisingrigid frameworks, a bulldozer having a blade and rearwardly extendinglimbs pivotally-mounted on the tractor adjacent said axle, a transversebar mounted on said frameworks and adapted to be carried into obliquepositions as the wheel frameworks swing irregularly on their pivotalmounting, a U-shaped beam pivotally mounted on the bar at its center,links pivotally connected to the ends of the U-shaped beam and to theblade, and means on the blade for holding the links rigid with respectto the blade for the purpose of maintaining the blade at a desiredelevation.

7. In combination, a tractor having track laying wheel structurespivotally mounted on the tractor adjacent their rear ends, saidstructures having forwardly extending rigid frameworks supporting. thetractor, a bulldozer pivotally supported from the tractor near thepivotal mounting of the wheel structures, and an equalizing linkagesupported by the frameworks of both wheel structures at a forwardposition thereon, said equalizing linkage comprising a pivotalconnection in the longitudinal direction of the tractor whereby thebulldozer remains substantially horizontal irrespective of differentialmovements of the forward portions of said frameworks.

8. A bulldozer comprising a blade and two rearwardly extending limbswhereby the blade may be pivotally mounted on a tractor, a bar rotatablymounted on the blade and extending longitudinally thereof, arms rigidlymounted on said bar an equalizer adapted to be connected to said tractorand connected to the rear ends of said arms, and a hydraulic cylinder onsaid blade for rotating said bar to adjust the elevation of the blade.

9. A bulldozer comprising a blade, a foot at each end of the bladeadapted to bear against the ground, long arms supporting said blade andadapted to be pivotally mounted on a tractor, and means at the front endof said bulldozer inaoraeae eluding a pivoted equalizer beam forsupporting the blade from the tractor.

l0. Abulldozer comprising a blade, a foot at each end of the bladeadapted to bear against the ground, long arms rigidly connected to saidblade and adapted to be pivotally mounted on a tractor, means adjacentthe front endoi said bulldozer including linkages, and a pivotedequalizer beam for supporting the blade from the tractor, and hydraulicmeans mounted on the bulldozer adapted to actuate said linkages to varythe height of the blade.

11. A bulldozer comprising a blade, long arms mounted on the rear end ofthe tractor sup-' porting said blade, and supporting means for each sideof said blade adjacent the forward end of the tractor including a beamadapted to rock tractor.

JOSEPH KUCHAR.

